Respiratory tract infections (RTIs) are infections that affect the respiratory tract, including body parts like the throat, airways, sinuses and lungs. These infections can be classified into two types, namely, upper respiratory infections and lower respiratory infections. Upper respiratory tract infections are caused by viruses that enter the human respiratory system. Some common upper respiratory infections are epiglottitis, common cold, pharyngitis, sinusitis, and laryngitis. Lower respiratory infections last longer and affect the lungs and airways. Viral infections of the respiratory tract can easily spread from one person to another through cough droplets or coming into contact with an infected surface. Cough, fever, sore throat, and swollen lymph nodes are some common symptoms of viral respiratory infections. Diagnosis of these infections involves tests like lung CT scan, sputum test, throat swab, etc. Treatments can involve pain relief medications, antihistamines and decongestants, which can help to relieve the symptoms. This book provides comprehensive insights into the viral infections of the respiratory tract. Researchers and students engaged in the study of these infections will be assisted by this book.